In a coking operation it is necessary to clean the edges of the coke-oven doors and doorjambs with each operation cycle. Thus each time a coke-oven door is removed and the charge is pushed out of the respective oven the doorjamb edges and the edges of the door must be cleaned so that the door can be replaced to make a good seal. This procedure is described in The Making, Shaping and Treating of Steel, edited by H. E. McGannon (Herbick & Held: 1971) at pages 129 sf.
The main problem with such devices is that the tarry carbon deposits that build up on the edges of the doors and doorjambs quickly foul the cleaning element. When a scraper is used such as described in German utility model 1,994,711 it is rapidly so heavily crusted with these carbonaceous deposits that it cannot clean properly. Thus the cleaning operation must be slowed down considerably to allow the fouled tool to do the job, or a potentially unsatisfactory cleaning job, which could lead to dangerous leaks, must be accepted. Otherwise the scraper must itself be periodically cleaned. None of these solutions is satisfactory.
The use of a rotary brush as described in German Pat. No. 2,332,027 does give satisfactory cleaning for a while at least, as it is somewhat more difficult to encrust with the tarry deposits, yet nonetheless with time even a large brush can become so heavily coated as to be ineffective. Cleaning the deposits off the brush is an even more onerous task than cleaning them off a scraper.
Finally it has been suggested in German printed patent application No. 2,143,595 to clean the door and the doorjamb edges wholly hydraulically with high-pressure water sprays. Such a system is extremely messy. Furthermore the deposits are normally water insoluble so that the water must work with a wholly hydraulic effect. The result is an often inadequate cleaning job.